Left ventricular cardiac pacing therapies generally rely implanting a lead in a venous structure of the left ventricle and stimulating the left ventricle using a single electrode or a bipolar pair of electrodes of the lead. Such pacing is referred to herein as “single site” pacing. More specifically, where a single electrode is used, the electrode configuration is known as a unipolar electrode configuration while where a bipolar electrode pair is used (usually a closely spaced pair), the electrode configuration is known as a bipolar electrode configuration. In either instance, these electrode configurations are considered single site and, hence, pacing that uses one of these electrode configurations is considered single site pacing.
While single site pacing has proven beneficial, multi-site pacing may, in some instances, be more beneficial. For example, a study by Ryu et al. (“Comparative effects of single- and linear triple-site rapid bipolar pacing on atrial activation in canine models”, Am J Physiol Heat Circ Physiol 289: H374-H384, 2005) tested the hypothesis that in the canine right atrium, bipolar, linear, triple-site rapid pacing creates more uniform propagation than bipolar, single-site rapid pacing and thereby minimizes or eliminates conduction block or delay (potential proarrhythmic effects that might otherwise be present due to rapid pacing). The study showed that, at rapid atrial pacing rates, both parallel and perpendicular linear triple-site pacing created more uniform linear impulse propagation and that single-site pacing created heterogeneous propagation in the presence of conduction abnormalities.
While multi-site pacing may be beneficial, multi-site pacing may require more energy when compared to single site pacing. Further, selection of multiple sites can be a more complex task compared to selection of a single site. As described herein, various exemplary techniques facilitate site selection and site optimization for right ventricular pacing, left ventricular pacing and/or bi-ventricular pacing. Various exemplary techniques can automatically optimize cardiac therapy using single site and/or multi-site pacing.